DATA DEPENDENT: Rodgers’ Liverpool v Klopp’s Liverpool

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In the last 5 years, Liverpool have had two title challenges. In 2013-14, Liverpool had a Luis Suarez-fuelled run, but ultimately ended up throwing the league away when they lost 2-0 to Jose Mourinho’s Chelsea in the game that saw Gerrard’s infamous slip. In 2018-19 the team finished one point behind Manchester City on 97 points, the 3rd highest total in Premier League history, largely due to a virtually immaculate defence led by Virgil Van Dijk. Both campaigns ultimately ended in heartbreak with Liverpool finishing behind Manchester City. However, scratch beneath the surface using the underlying numbers and both seasons were actually very different.

Going forward

Liverpool came from nowhere to hit their stride in December 2013 with a 5-1 win at White Hart Lane. Prior to that, no one side had grabbed the league by the scruff of the neck. The 2014 portion of the season featured demolitions of Arsenal Wenger’s Arsenal and various wonder goals by Suarez, most notably against Norwich City. Suarez ended up with 31 goals and also added 13 assists. Suarez’s strike partner, Daniel Sturridge, was no slouch either, weighing in with 21 goals, including a glorious lob over the Everton keeper in the derby at Anfield.

The side finished the season with a total of 101 goals. At the time, this was the most goals scored by side not to win the league. They also only took 638 shots, resulting in an insane conversion rate of 16% (the league average is 13%). Only 19% of their shots were blocked, against a league average of around 23%.

According to Statsbomb, by the 37th game of the season, Liverpool had notched up 99 actual goals against just 83.5 expected goals, resulting in a ratio of 119%. The shot conversion and expected goals ratios indicates that Liverpool’s finishing was not only phenomenal, but also completely unsustainable. To compound this theory, according to a model created by Statsbomb which features several simulations, Liverpool only had a 7.25% chance of scoring 95 goals.

In the summer of 2018, most Liverpool fans would have settled for some sort of title challenge and a Top Four finish. What they witnessed was a controlled machine of a team that could collect points without having to blow opponents away. Liverpool were neck and neck with City from day one and at one stage were 7 points ahead. But Mohamed Salah “only” finished the season with 22 goals, as did Sadio Mane. Goals from midfield were scarce. Xherdan Shaqiri picking up the most with a mere 6.

Liverpool finished the season with 12 less goals than Brendan Rodgers’ side with 89, off 79 expected goals, resulting in a ratio of 113%. This represents a much more sustainable attacking model, especially when you consider that Salah had picked up a likely unrepeatable 32 goals the previous season.

Fortress Anfield

While Liverpool’s 2013-14 attack was on fire, the same could not be said of the defence. Marshalled by Martin Skirtel, with a supporting cast of Sakho and Moreno, Liverpool’s backline conceded a whopping 50 goals in all competitions. They were not helped by having an aging Steven Gerrard playing in front of them in the defensive midfielder role. Again, by the 37th game, the goalkeeper, Simon Mignolet had conceded 44 goals with only 38.4 expected goals against, an efficiency of 87% (the worst in the league). If you want to win the league, you need your goalkeeper to be outperforming expected goals against by making above average saves.

After Gerrard’s slip against Chelsea, the Belgian was left floundering in the one-on-one against Demba Ba and ended up conceding the goal that provided the killer blow to Liverpool’s season. All in all, Liverpool’s defensive unit gave up a massive 42 defensive errors.

Fast forward to the 2018/19 season and we see a backline consisting of the world class talents of Virgil Van Dijk and Alison Becker in goal, supported by the more than able Trent Alexander Arnold, Joel Matip, and Andy Robertson. Between them, the back five conceded just 22 goals resulting in only 1 loss all season. Liverpool limited their opposition to 29.2 expected goals against, meaning that the goalkeeper, Alison, outperformed his expected goals against by 7.2 with an efficiency of 133%. The keeper made notable one-on-one saves against teams such as Chelsea as well a key save against Burnley in the dying minutes.

Sustainability

Contrast Alison’s expected goals conceded ratio of 133% with Mignolet’s 87%, and we begin to get the picture. Liverpool now have a truly elite defence, meaning that crazy amounts of goals are not required to win points. There is now much less luck involved in Liverpool’s play. And if the midfield fails to protect the defence, Liverpool have centre backs and a goalkeeper with proven track records to stop attacks.

After the 2013/14 season, Luis Suarez was sold and Daniel Sturridge faced long term injuries. Steven Gerrard required phasing out and Brendan Rodgers ran out of ideas.

In 2019, Liverpool have a relatively young squad that they can build on. They have been lucky with injuries to the front three but are likely to invest in an elite 4th attacker. Add other rock-solid defenders such as Joe Gomez to the mix and the future looks very bright indeed for Liverpool.